Time-lapse Seismic Difference Inversion And Application

During time-lapse seismic,it is of great significance to conduct dynamic characterization of oil reservoir.This will not only have some understanding of the distribution of oil and gas in during the exploitation of the working area,but also provide theoretical basis for subsequent exploration and development.In the process of reservoir dynamic characterization,the difference elastic parameters obtained by difference inversion,the parameter results obtained by reservoir forward model,and the difference value of seismic attributes are necessary.In order to obtain the changes of elastic parameters during time-lapse seismic,the pre and post stack difference inversion are needed.In this paper,the methods of difference inversion for pre and post stack seismic data are mainly studied,in which the pre-stack difference inversion is mainly based on the exact Zoeppritz equation,which avoids the introduction of error.During the difference inversion,the objective function is constructed based on the Bayesian framework,and the differential Laplace blocky constraint is introduced to control the boundary of the difference seismic data.Since the regularization parameter is introduced during inversion,the GCV and improved L-curve methods are used to calculate parameters adaptively,which will avoid errors caused by artificial setting.And results of numerical tests show better accuracy,stability and efficiency with the GCV solution to get the regularization parameter.So,this method can be applied to actual working area for time-lapse seismic difference inversion.According to the difference elastic parameters obtained from inversion and the given actual data,the multi-source information fusion method can be used to characterize the reservoir dynamic change.In this paper,the applicability of RGB and fuzzy logic fusion methods for fusion are compared through numerical tests,and the results of fuzzy logic method is verified to be more consistent with the actual data.The fusion result has a good description of the area where oil and gas change violently during time-lapse seismic,which will provide data for exploration and interpretation and has guiding significance for later development.